For various reasons, including reasons relating to vehicle safety and fuel economy, it is important to be able to determine the pressure of each pneumatic tire of a motor vehicle, and, if possible, to be able to do so on a continuous basis. For most containment reasons, it is also important to be able to do so without the need to incorporate additional instrumentation for that purpose. In vehicles incorporating an ABS system, a pulse signal from the ABS system can be used to determine the rotational speed or angular velocity of each wheel. Published U.S. patent application Ser. No. 2003/0172728 A1 (Gustafson et al.) discloses a system for using the angular velocity of the wheels of a vehicle, and parameters indicative of lateral movement of the vehicle, to estimate vehicle tire pressure. The need to use vehicle lateral dynamics in determining vehicle tire pressure does, however, require a gyro to sense the yaw rate of the vehicle, and this is an item of expense that, desirably, is to be eliminated whenever possible.